Keywords in C#

Keywords or reserved words in C# programming are language-specific words that have special meanings. You cannot use them for names of variables or functions.

Keywords are predefined, reserved identifiers that have special meanings to the compiler. They cannot be used as identifiers in your program unless they include @ as a prefix. For example, @if is a valid identifier but if is not because if is a keyword.
The first table in this topic lists keywords that are reserved identifiers in any part of a C# program. The second table in this topic lists the contextual keywords in C#. Contextual keywords have special meaning only in a limited program context and can be used as identifiers outside that context.
Generally, as new keywords are added to the C# language, they are added as contextual keywords in order to avoid breaking programs written in earlier versions.

Keywords

abstract	as	base	bool	break
byte	case	volatile	while	void
catch	char	checked	class	const
continue	decimal	default	delegate	do
double	else	enum	event	explicit
extern	false	finally	fixed	float
for	foreach	goto	if	implicit
in	in	int	interface	internal
is	lock	long	namespace	new
null	object	operator	out	out
override	params	private	protected	public
readonly	ref	return	sbyte	sealed
short	sizeof	stackalloc	static	string
struct	switch	this	throw	true
try	typeof	uint	ulong	unchecked
unsafe	ushort	using	virtual
aaaaaaaa	aaaaaaaa	aaaaaaaa	aaaaaaaa	aaaaaaaa

Contextual Keywords

A contextual keyword is used to provide a specific meaning in the code, but it is not a reserved word in C#. Some contextual keywords, such as partial and where, have special meanings in two or more contexts.

add	alias	ascending	async	await
descending	dynamic	from	get	global
group	into	join	let	orderby
partial	partial	remove	select	set
value	var	where	where	yield

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